President Trump addresses the nation

Image Source: Shealah Craighead / The White House / MGN

WASHINGTON, D.C. (ABC NEWS) - President Donald Trump used his first Oval Office address to the nation to urge Congress to address what he called a “growing humanitarian and security crisis” at the southern border.

"This is a humanitarian crisis, a crisis of the heart, a crisis of the soul," he said.

President Donald Trump deliver a televised address to the nation from his desk in the Oval Office about immigration and the southern U.S. border at the White House in Washington, Jan. 8, 2019.

Trump urged Congress to take up his administration's request for $5.7 billion in border wall funding, along with millions for additional detention beds and new screening technology.

"These are the resources they have requested to properly perform their mission and keep America safe. In fact, safer than ever before," he said of border agents and law enforcement.

Trump claimed the border wall would "quickly pay for itself," and that it would be paid for indirectly through the new trade deal with Canada and Mexico, an assertion disputed by economists.

He implored Congress to think of the families of Americans murdered by illegal aliens, without quantifying the figure.

"I have met with dozens of families whose loved ones were stolen by illegal immigrants. I have held the hands of the mothers and embraced the grief stricken fathers," he said. "I will never forget the pain in their eyes, the tremble in their voices, and the sadness gripping their souls. How much more American blood must we shed before congress does it's job?"

Trump then tweeted video of his address.

The president's address, aimed at building public support for his signature campaign issue -- his proposed border wall -- comes on the 18th day of a partial government shutdown over his demand that Democrats agree to billions of dollars to pay for the wall.

He was followed by a televised joint response from Democratic leaders, House Speaker Nancy Pelosi and Senate Minority Leader Chuck Schumer, who adamantly oppose paying for a wall and are demanding Trump agree to re-open the government.